Archive: III-V Nanowires for Optoelectronics

2023

• Carrier recombination in highly uniform and phase-pure GaAs/(Al,Ga)As core/shell nanowire arrays on Si(111): Mott transition and internal quantum efficiency
  Authors: M. Oliva, T. Flissikowski, M. Góra, J. Lähnemann, J. Herranz, R. B. Lewis, O. Marquardt, M. Ramsteiner, L. Geelhaar, O. Brandt 
  Published in: ACS Appl. Nano Mater., 6, 15278–15293 (2023) 
  DOI: 10.1021/acsanm.3c03242
   
• Growth kinetics and substrate stability during high-temperature molecular beam epitaxy of AlN nanowires
  Authors: P. John, M. Gómez Ruiz, L. van Deurzen, J. Lähnemann, A. Trampert, L. Geelhaar, O. Brandt, T. Auzelle 
  Published in: Nanotechnology, 34, 465605 (2023) 
  DOI: 10.1088/1361-6528/acefd8 
   
• Density control of GaN nanowires at the wafer scale using self-assembled Si patches on sputtered TiN(111)
  Authors: T. Auzelle, M. Oliva, P. John, M. Ramsteiner, L. Geelhaar, O. Brandt
  Published in: Nanotechnology, 34, 375602 (2023) 
  DOI: 10.1088/1361-6528/acdde8
   
• A route for the top-down fabrication of ordered ultrathin GaN nanowires
  Authors: M. Oliva, V. M. Kaganer, M. Pudelski, S. Meister, A. Tahraoui, L. Geelhaar, O. Brandt, T. Auzelle 
  Published in: Nanotechnology, 34, 205301 (2023) 
  DOI: 10.1088/1361-6528/acb949
   
• Sequential directional deposition of one-sided (In,Ga)N shells on GaN nanowires by molecular beam epitaxy
  Authors: D. van Treeck, J. Lähnemann, G. Gao, S. Fernández Garrido, O. Brandt, L. Geelhaar 
  Published in: APL Mater., 11, 091120 (2023) 
  DOI: 10.1063/5.0168786

• Carrier Recombination in Highly Uniform and Phase-Pure GaAs/(Al,Ga)As Core/Shell Nanowire Arrays on Si(111)

  This work reports the growth of highly uniform, phase-pure GaAs/(Al,Ga)As nanowire arrays on silicon using molecular beam epitaxy. Their optical analysis reveals a sharp Mott transition and high quantum efficiency, highlighting the potential of these nanowires for efficient light-emitting devices integrated directly on silicon.

• The azimuthal cell arrangement in molecular beam epitaxy drastically affects the luminescence efficiency of nanowire shells

  The chamber geometry of a system for molecular beam epitaxy (MBE) is known to affect technical aspects such as the macroscopic deposition homogeneity across a wafer. However, for the microscopic mechanisms governing the growth of thin films on a planar substrate, the chamber geometry does not play any role. In marked contrast, we show here that the luminescence efficiency of (In,Ga)As/GaAs shell quantum wells grown around GaAs nanowires changes by more than two orders of magnitude depending on the relative position of the As cell compared to the group-III cells.

• Understanding exciton recombination in GaN nanowires

  A strong asset of bottom-up nanowires and related nanowire heterostructures is the enhanced surface strain relaxation that delays the onset of plastic relaxation. GaN nanowires that are free of dislocations can be directly grown on technologically relevant substrates such as silicon or metals. Yet, in spite of their high structural perfection, the electron-hole recombination in these nanoscopic structures remains predominantly nonradiative, even at cryogenic temperature. Here, we provide first evidence that the efficient nonradiative channel does not take place at point defects located at the nanowire surface or in the bulk, but stems instead from field-ionization of the exciton in the surface electric field.

• GaAs-based nanowire heterostructure for light generation in the telecommunication O band on Si

  The monolithic integration of light emitters on Si remains an important technological challenge for the development of intra-chip optical connections, as well as inter-chip connections. In this context, GaAs nanowires grown on Si substrates offer great potential, but their effective use for Si photonics technologies requires operation in the Si transparent window, with special relevance of the telecommunication bands for potential data transfer applications. Here, we present a novel coaxial nanowire heterostructure to extend the emission range of GaAs-based nanowire devices into the telecommunication O band.